SURGICAL CONDITIONS
General Surgery
Cancer
What is Cancer?
Cancer is a disease that results from abnormal growth and division of cells that make up the body's tissues and organs. Under normal circumstances, cells reproduce in an orderly fashion to replace old cells, maintain tissue health and repair injuries.
However, when growth control is lost and cells divide too much and too fast, a cellular mass -or "tumour" -is formed.
If the tumour is confined to a few cell layers and it does not invade surrounding tissues or organs, it is considered benign. By contrast, if the tumour spreads to surrounding tissues or organs, it is considered malignant, or cancerous. In order to grow further, a cancer develops its own blood vessels and this process is called angiogenesis.
When it first develops, a malignant tumour may be confined to its original site.If cancerous cells are not treated they may break away from the original tumour, travel, and grow within other body parts. This process is known as metastasising. The resultant remote cancer deposits are called metastases or secondaries.
Click on the below links to find more about the individual cancers.
Oesophageal cancer
Oesophageal cancer (also called cancer of the oesophagus) is a malignant tumour that grows in the lining of the oesophagus. The oesophagus (the gullet) is the tube that carries food from the mouth down into the stomach using a series of muscular movements.
Types of oesophageal cancer
Two types of cancer, squamous cell carcinoma and adenocarcinoma, make up 90 per cent of all oesophageal cancers. Oesophageal cancer can occur in any section of the oesophagus. Most cancers in the top part of the oesophagus are squamous cell cancers. They are called this because the cells lining the top part of the oesophagus are squamous cells. Squamous means scaly.
Most cancers at the end of the oesophagus that joins the stomach are adenocarcinomas. Adenocarcinoma of the oesophagus used to be rare. However, in the last 20 years its incidence has increased dramatically in the Western world. The reasons for this are not completely clear. It is related, at least in part, to the rise in obesity and an increasing incidence of oesophageal reflux (heartburn). This can result in a premalignant change in the lining cells, called Barrett’s oesophagus. Not everyone with Barrett’s develops oesophageal cancer, but it does increase the risk significantly. For more information about Barrett’s go to barrettsinfo.com
The most common symptom of oesophageal cancer is difficulty swallowing (dysphagia). Unfortunately the cancer is often quite advance by the time this occurs and patients seek help. Difficulty swallowing should never be ignored – prompt investigation is vital. There are other causes of dysphagia which can often be treated easily.
If an oesophageal cancer is diagnosed, the next step is to “stage” the cancer ie see if there is any evidence that the cancer has already spread. I normally use CT scanning and often PET scanning to do this. Laparoscopy is also sometimes required.
Current evidence suggests that the first treatment for most oesophageal cancers should be a course of chemotherapy. This often shrinks the primary cancer and also may kill cells that have spread beyond the primary cancer, but which cannot be detected on the staging investigations. The chemotherapy normally lasts 2-3 months and surgery is done about 2 weeks later. The operation of oesophagectomy (or gastro-oesophagectomy) is a major one and patients need to be as fit as possible. If you are a smoker , it is imperative that you stop. During the time you are having chemotherapy you should try and stay fit (or get fit) by walking for at least an hour a day. If there is any likelihood of heart disease due to previous smoking, family history, obesity or other factors, I will often arrange a preoperative thallium stress test.
The surgery involves two incisions. The first cut is in the upper abdomen and through this, I free up the stomach and enlarge its opening (pyloroplasty procedure). A feeding tube is inserted into the small intestine so that liquid feed can be delivered to to the gut until such time as the patient can eat adequately. The second incision is in the right side of the chest. The oesophagus is removed and the stomach is pulled up through the diaphragm and then joined to the small remnant of oesophagus, high in the chest.
You will initially be sent to the Intensive Care Unit and will stay 1-2 days there. In general you are likely to spend about 14 days in hospital, all being well. It takes many weeks to fully recover from an operation of this magnitude. Nonetheless, if all goes well, and the cancer is cured, your long term quality of life is generally very good.
Initially it is difficult to eat and you will have no appetite. For the first few weeks, supplementary liquid protein supplements are given, both through the feeding tube, and then by mouth. You will almost certainly lose weight for the first few months. The stomach is often slow to empty and its capacity is reduced. Small, frequent meals are required and these should all be of high nutritional value. The dietitian and I will advise you accordingly.
Some people experience problems with “Dumping Syndrome” due to the lack of control of stomach emptying after this surgery. Dumping syndrome may leave you feeling faint or give you diarrhoea soon after eating. It often improves over time and can be helped with appropriate food choices. To download a PDF file about dumping, click here:
Gastric Cancer
Gastric (stomach cancer) is one of the most common cancers in the world. However, it has become less common in Australia in the last 50 years. This is due to a number of factors, including improved nutrition and sanitation. Many stomach cancers are related to chronic infection with the germ Helicobacter pylori, which is also a cause of many benign ulcers. This infection is less common in modern Australia than in many other parts of the world. The decreasing presence of this germ is one factor accounting for the decrease in gastric cancer, along with an increased availability of fresh food, with decreased reliance on smoked, pickled and preserved foods.
The exception to this overall decreasing incidence of gastric cancer is cancer of the upper part of the stomach, known as the gastric cardia. Cancers in this area are increasing in frequency, just like cancers of the lower oesophagus. Once more, obesity seems to be part of the problem, but does not explain everything. Research is currently being done to determine what other factors in our diet may be contributing to this problem.
Gastric cancer often causes the same symptoms as benign disease in its early stages. Indigestion, anaemia or heartburn can all be caused by cancer. It is important therefore that these symptoms are never treated long term without determining if there is a serious underlying cause. Drugs that suppress gastric acid will often make the symptoms of gastric cancer improve temporarily, potentially delaying the diagnosis.
The mainstay of treatment for gastric cancer is surgery, with removal of part, or sometimes all of the stomach. The remainder of the stomach or the lower part of the oesophagus is then joined to the small intestine, so that you can continue to eat.
Chemotherapy is sometimes given prior to surgery to reduce the size of the cancer and hopefully kill microscopic deposits that may have spread elsewhere. Alternatively, chemotherapy, sometimes combined with radiotherapy may be recommended afterwards.
Obviously there can be difficulties maintaining nutrition if part or all of the stomach has been removed. However, in the long term, most people have a surprisingly good quality of life in this regard – the body adapts remarkably well. Just as with oesophagectomy, the principles of eating are to have small, frequent meals of high nutritional value. Vitamin supplements and iron may be recommended. If the whole stomach has been removed it will be necessary to have an injection of Vitamin B12 every 2 months as this important vitamin cannot be absorbed if you have no stomach. People who have undergone gastrectomy (stomach removal) may also be prone to dumping syndrome, which can lead to faintness and/or diarrhoea after eating. This tends to settle with time and can be improved with suitable food choices. To download a PDF on dumping syndrome, click here:
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